The present invention relates to burners generally, and more particularly to a high intensity burner construction suitable for use in conjunction with variously configured air heaters.
A typical large industrial slurry dryer is shown in FIG. 1 in conjunction with a ring-shaped air heater and burner combination. The dryer assembly 1 includes a funnel shaped housing 2 from which slurry pump and atomizer 3 discharge the slurry from the small diameter end of rotating nozzle 4 into a drying space 5 where the slurry is dried and the dried particles 6 are gravitationally separated from the water 7 and are dropped into a hopper (not shown) for removal. Fins 8 are angularly oriented such that when rotated fins 8 draw hot 700.degree.-1000.degree. C. gas-air from plenum 9, through annular opening 10, and along the conical outside of housing 2 through conical ring duct 11. The hot gas-air then exits duct 11 as it is directed toward the slurry discharge opening of nozzle 4 where it is mixed with the atomized slurry to drive off the water.
Among the drawbacks of conventional burners are No.sub.x emissions, complex constructions to prevent flame propagation into the burner, and low turn down rates. Although attempts have been made to reduce NO.sub.x emissions and prevent flame propagation into the burner, while maintaining the desired turn down rate, no single system having a simple construction has achieved all three of these results.